The present invention relates to a disposition structure of engine functional components for a vehicle, such as a radiator and an electronic control device.
In these days, light-weight and compact vehicles have been desired to improve the fuel economy, and a low front nose has been designed for vehicles to reduce the air resistance of vehicle. As a result, since the space of an engine room of vehicles tends to be smaller and shallower, it has become difficult to properly layout the disposition of engine functional components in the engine room.
Japanese Patent Laid-Open Publication No. 2001-234746 discloses an exemplified disposition of the engine, radiator, air cleaner and electronic control device for the vehicle equipped with the slant nose. In this disposition, the radiator is disposed substantially horizontally in front of the engine such that its upper end is located forward, and the air cleaner is located just above the radiator.
Herein, the electronic functional components such as an engine control unit and a power train control module, which are disposed in the engine room, are apt to be caused an functional trouble by an excessively increased temperature of them. However, since these components produce the heat themselves and receive a radiant heat from the engine, there is a concern that these components could not be cooled properly in the engine room.
Thus, the above-described patent publication proposes that the electronic control device be disposed at a portion behind an wheel house located outside a front side frame, which is relatively away from the engine, and an opening hole be formed at the wheel house in front of the electronic control device, so that the outside air can be taken in from the opening hole and the device can be cooled by the air.
However, in the event that the space in the engine room becomes smaller and shallower, there exists a case where an enough space for disposing the electronic control device behind the wheel house disclosed in the above-described publication may not be obtained. In this case, the electronic control device needs to be disposed at another place in the engine room.
Also, there occurs an air flow from the front to the rear in the engine room which is caused by the cooling air from the cooling fan or the outside air during a vehicle driving. Thus, the radiant heat from the engine is apt to stay rearward and upward in the engine room. Accordingly, it is preferable from view points of heat environment in the engine room that the electronic control device is disposed in front of the engine.
However, since there are provided some components such as the radiator, air cleaner, and battery in the space in front of the engine, it is not so easy to provide the space for the electronic control device in front of the engine, particularly in the narrow engine room.